RIT Factory CMOS Electrical Test Dr. Lynn Fuller and David Pawlik

Transcription

1 ROCHESTER INSTITUTE OF TECHNOLOGY MICROELECTRONIC ENGINEERING RIT Factory CMOS Electrical Test Dr. Lynn Fuller and David Pawlik Webpage: 82 Lomb Memorial Drive Rochester, NY MicroE Webpage: Revision Date: CMOSTEST_Manual.ppt Page 1

2 INTRODUCTION Motivation Most students taking Factory class are not yet familiar with the test equipment used in the test lab. Goal Create a PowerPoint Manual, and electrical tests, so that most people will be able to easily perform the electrical tests, and extract the necessary data. Assumptions Operator has a base knowledge of: 1) The electrical tests being done 2) How to extract necessary information from the generated curves. Page 2

3 TEST EQUIPMENT Semi-automatic Prober Automatic Prober Page 3

4 TEST EQUIPMENT Manual Prober Page 4

5 TEST STATION Light Source Switch Matrix PC Interface CCD Camera Microscope HP4145 tester Semi-Auto Probe Station Page 5

6 HP4145 PRESS THE ON BUTTON TO POWER UP Data Transfer & Standby LED s Screen (Displays useful information and options) On Button Measurement LED (turns on when measurement is in progress) Press the On Button to Power Up Page 6

7 SWITCH MATRIX - PRESS THE ON BUTTON TO POWER UP Switch Matrix Indicator Light Pen On Button Copy Button Press the On Button to Power Up Page 7

8 PC DESKTOP Log onto PC, locate the two icons shown below, Double click on ICS icon Osprey Camera Software Interactive Characterization Systems HP4145 tester interface software (used to setup and execute all electrical tests) Page 8

9 ICS SETUP Step 2 Step 3 Details on next page Start ICS ICS 1. Click ok for any window that pops-up 2. Select GPIB card (NI 32 Thunk), Okay 3. Select tester (HP4145), Connect 4. Configure then Poll (make sure PC talks to the tester, watch communication LEDs) Page 9

10 ICS SETUP DETAILS ICS Setup 1. Select GPIB card (NI 32 Thunk) 2. Select tester (HP41545) 3. click Config button on the Instruments window then Poll Page 10

11 ICS LOAD ELECTRICAL TESTS Load electrical tests 1. Download ICS_Test_Setups.dat file from Dr. Fuller s webpage: 2. Right Click, Save As, Save to desktop Location highest level, then [docume~1], then [your username], then [desktop] 3. In ICS Click File Import 4. Navigate to the desktop C:/documn~1/username/desktop 5. Open FAC_SUB.dat Page 11

12 LIST OF ELECTRICAL TESTS Test Name Description Parameters to be extracted Units VDP-POLY Poly Van Der Pauw Poly Sheet Resistance ohms/square VDP-MET Metal Van Der Pauw Metal Sheet Resistance ohms/square VDP-N N+ Van Der Pauw N+ Sheet Resistance ohms/square VDP-P P+ Van Der Pauw P+ Sheet Resistance ohms/square VDP-PWELL P-well Van Der Pauw P-Well Sheet Resistance ohms/square CBKR-N CBKR Metal to N+ silicon Specific Contact Conductance for metal to N+ silicon mmho/µm2 CBKR-P CBKR Metal to P+ silicon Specific Contact Conductance for metal to P+ silicon mmho/µm2 CBKR-POLY CBKR Metal to Poly Specific Contact Conductance for metal to Poly mmho/µm2 NFAM NMOS Family of Curves Lambda 1/Volts NVT NMOS ID - Vgs Max gm mho/µm of channel width Vtn Volts NSUB NMOS Sub Threshold ID-Vgs Sub Threshold Slope mv/decade Imax/Imin # of decades PFAM PMOS Family of Curves Lambda 1/Volts PVT PMOS ID - Vgs Max gm mho/µm of channel width Vtn Volts PSUB PMOS Sub Threshold ID-Vgs Sub Threshold Slope mv/decade Imax/Imin # of decades NFIELD NMOS Family of Curves N Well Field Vt Volts PFIELD PMOS Family of Curves P Well Field Vt Volts INV Inverter Vout versus Vin Imax Amps Vinv, Voh, Vol, Vih, Vil Volts Page 12

13 ICS SELECTING AND RUNNING A TEST Measure button Test selector Display the Measure window 1. Click the Measure button (8 th from the left) 2. Use drop-down box to select a test PFAM NVT PVT NSUB PSUB NFAM VDP-POLY, VDP-METAL, etc. CBKR-N, CBKR-P, CBKR-POLY INV FIELD_NMOS_VT FIELD_PMOS_VT 3. Click the Single button to run the selected electrical test Run Single Page 13

14 PROBE STATION SHOULD ALWAYS BE POWERED ON Zoom Stage Micrometer (moves stage up and down) Focus 2 Focus 1 Thumb Screws Probe Card Wafer Stage Page 14

15 INSERTING PROBE CARD Choose Probe Card There are 2 types: 1) 10 pin card, & 2) 12 pin card Sub-CMOS: 10 pin probe card DAC lots: 12 pin probe card Adv-CMOS: 10 pin probe card Probe Card Slot Remove Probe Card (If one is in the probe station already) 1. Twist Micrometer up (couple turns) 2. Loosen 4 thumb screws 3. Remove card Insert Desired Probe Card 1. Push card into the slot 2. Tighten 4 thumb screws Probe Card Page 15

16 PROBE STATION SHOULD ALWAYS BE POWERED ON Home & Load/Center Buttons Y-Axis & X-Axis indexing distances Index/Jog toggle Switch Index: move the stage a large distance indicated by the user. Jogg: moves the stage a small distance. Probes Up/Down Vacuum On/Off Thumb Screws Wafer Stage Stage Movement Probe Card Page 16

17 LOAD WAFER Move Stage to the Load Position Press the Load/Center button (moves stage out) Load the Wafer Make sure the vacuum switch is turned off Load the wafer onto the center of the chuck Wafer flat towards front of the tool Turn on the vacuum Press the Home button Wafer is loaded and ready for viewing using Osprey Page 17

18 OSPREY VIDEO IMAGING SETUP Turn the Light on Turn the dial on the light source clockwise until optimal brightness is achieved Start Osprey Software on your Desktop Click close on the window that pops-up. Second window is a video image of the microscope imaging. Window cannot be resized but magnification (zoom) can be changed Adjust zoom and focus Zoom Focus 2 Focus 1 Page 18

19 SETUP STAGE HIGHT Maneuver probes over empty street 1. Set Index/Jog switch to Jog 2. Use arrow buttons appropriately 3. Stop when over street (empty space between die) Make probes contact Aluminum in the street 1. Toggle Probes down (set separate/contact switch to contact) 2. Use micrometer to move probe card down 3. When probes slide (very small amount) stop moving micrometer 4. Toggle probes up (separate) 5. Move station small amount, and look for probe marks - Black marks where the probes scratched the aluminum - Marks should be small elongated dots (Ex. ) 6. Repeat As needed (move micrometer up if needed) Page 19

20 SWITCH MATRIX Switch Matrix Indicator Light Pen On Button Copy Button Turn on Switch Matrix (should be on from page 5) Use Light wand to activate different switches Point wand at a circle on the indicator. Push button on the light wand. LED should toggle on and off. Columns indicate pin number on the probe card. Rows indicate SMU number (A = SMU 1, B = SMU 2, etc.). Push the Copy Button. Activates the appropriate switches (LED is on) so that indicated probe pins and SMUs are connected. Leave this button turned on. Page 20

21 STANDARD PROBE CARDS Pad Probe Card Pad Probe Card Wafer Chuck HP 4145 Test Fixture Numbers indicate switch matrix column Page 21

22 SUB-CMOS MIXED CMOS TEST CHIP Layout of CMOS test chip for microelectronic engineering manufacturing courses. This chip has transistors down to 0.5 µm gate length, a variety of test structures, digital and analog circuit building blocks including A-to-D and D-to-A converters, operational amplifiers, transconductance amplifiers, and filters of various types. Dr. Lynn Fuller, Lisa Bonanno 2003 Page 22

23 SUB-CMOS Die Photograph Page 23

24 ADVANCED CMOS TEST CHIP Page 24

25 SPICE PARAMETRIC CMOS TEST CHIP Page 25

26 DAC 2003 PROJECT CHIP Page 26

27 GENERAL TEST INSTRUCTIONS Test die in the center of the wafer, then upper left, upper right, lower right, and lower left (about ½ way between center and edge). Extract parameter values from the test results. Create a PowerPoint document from test_results.ppt master (see example data powerpoint a few pages below) on Dr. Fullers webpage at (save as) record Lot#, Wafer#, Die location (center, top left,etc), pictures of die, test results graphs, extracted parameters and comments. to Dr. Fuller at [email protected] Test 01 Van Der Pauw and CBKR. Record Average of five tests Test 02 Transistors, test small transistors (L=2µm for SMFL, L=1µm for Sub-CMOS and Adv-CMOS). Record results in power point document. Test 03 Inverters, Ring Oscillator. Record Average of five tests. Test 04 NMOS VT wafer map Page 27

28 GENERAL TEST INSTRUCTIONS Substrate or Well Connections: Most of the test structures incorporate diffusions. In Resistors, Van der Pauw s and Transistors the junctions between the diffusions and the substrate/wells are normally never forward biased. As a result the test engineer needs to evaluate the applied test voltages and connections to the substrate/wells and connections to the diffusions to ensure proper bias conditions. For example: a P+ Van der Pauw in an N-type Well requires that the Well connection always have the highest positive voltage that is applied. If a separate (5 th pad) connection is available (not often because there are only 4 SMU s) that can be set to a high voltage. Otherwise the substrate is normally connected to one of the four pads of the Van der Pauw. This pad can be swept with positive voltage thus keeping the substrate/well junction reverse biased. Page 28

29 GENERAL TEST INSTRUCTIONS Each test requires you to: 1. Find the structure you want to test 2. Place the probes 3. Open the test by restoring the testname -1 (example PFAM-1) in ICS, view the test setup to see what SMU s do what. 4. Set the switch matrix for the HP4145 SMU s to the probes you are using, consistent with the test setup. 5. Edit the graph by making changes in the title, moving the cursors to the correct location 6. Copy the plot using ctrl print screen, (paste into word, copy from word to power point, crop and paste in correct location) 7. Extract the data, such as threshold voltage or LAMBDA and enter the value in the data table in the powerpoint 8. Save the powerpoint, minimize the data plot on ICS 9. When done the powerpoint to [email protected] Page 29

30 TE01 Van Der Pauw and CBKR Page 30

31 VAN DER PAUW TEST STRUCTURES FOR SHEET RESISTANCE I I Rs V1-V2 V1 V2 I I I Rs = (V1-V2) P I ln 2 V1 V2 Page 31

32 CROSS BRIDGE KELVIN RESISTANCE TEST STRUCTURES FOR CONTACT RESISTANCES Gc V1-V2 V1 I W1 W2 V2 I I Rc = (V1-V2) I ohms Gc = I 1 (V1-V2) W1 x W2 mhos/µm 2 Page 32

33 TE01 Test Structures for SUB-CMOS Process MIXED Product Then Here Start Here Page 33

34 INVERTERS, VAN DER PAUW AND CBKR Lot Number = F Wafer Number = D4, Die Location R=, C= Inverter Poly Van Der Pauw M1 Van Der Pauw N+ Van Der Pauw P+ Van Der Pauw P-Well Van Der Pauw M1 to Poly CBKR M1 to N+ CBKR M1 to P+ CBKR

35 EXTRACTED PARAMETERS FROM INVERTERS, VAN DER PAUW AND CBKR Lot Number = F Wafer Number = D4, Die Location R=, C= Contact Gs CBKR Inverter P+ 42 mmho/µm 2 VinL 2.4 V N+ poly 8 37 mmho/µm 2 mmho/µm 2 VinH VoL VoH V V V # Stages Ring Oscillator 73 Vdd=5V Vinv Imax Gain V ma Period 104 nsec D0=ViL-VoL 2.0 V td nsec D1=VoH-ViH 1.5 V Rhos Van der Pauw Gain OpAmp None P+ 115 Ohms Offset None mvolts N+ 5.8 Ohms GBW None Hz well 614 Ohms VIA CHAIN Poly 20.0 Ohms M1-P+ None ohms Al Ohms M1-M2 None ohms

36 TE01 Test Structures for SUB-CMOS Process MIXED Product Van Der Paw: Metal Van Der Paw: Poly Page 36

37 TE01 Test Structures for SUB-CMOS Process MIXED Product Cross Bridge Kelvin : N + P + POLY Van Der Paw: N + D/S Van Der Paw: P Well Van Der Paw: P + D/S Page 37

38 TEST SET UP FOR POLY VAN DER PAUW (SUB- CMOS, MIXED) CHIPS Test Name: VDP-POLY SMU1 SMU2 SMU3 SMU Switch matrix rhos R V1-V2 SMU1 SMU2 I SMU3 Place Rochester a cursor Institute on of Technology the graph here to extract rhos value SMU4 USER F I1 Sweep 0.1 to 5 Volt I2 Mode I=0, Measure V1 V1 Com V2 Mode I=0, Measure V2 Rhos = = (V1-V2)/I1 / I Page 38

39 TEST SET UP FOR METAL VAN DER PAUW SMU1 SMU2 SMU3 SMU4 Test Name: VDP-MET Switch matrix R V1-V rhos SMU1 I1 Sweep 0.05 to 5 Volt I SMU2 SMU3 I2 V1 Mode I=0, Measure V1 Com Place Rochester a cursor Institute on of Technology the graph here to extract rhos value SMU4 USER F V2 Rhos Mode I=0, Measure V2 = = (V1-V2)/I1 / I Page 39

40 TEST SET UP FOR N+DS VAN DER PAUW SMU1 SMU2 SMU3 SMU4 Test Name: VDP-N Switch matrix SMU1 I1 Sweep 0-10mA SMU2 I2 Com SMU3 V1 Mode I=0, Measure V1 SMU4 V2 Mode I=0, Measure V2 USER F Rhos = (V1-V2)/I R V1-V2 rhos I Place a cursor Rochester Institute on the of Technology graph here to extract rhos value Page 40

41 TEST SET UP FOR PWell VAN DER PAUW Test Name: VDP-PWell SMU1 SMU2 SMU3 SMU Switch matrix rhos R V1-V2 Place Rochester a cursor Institute on of Technology the graph here to extract rhos value I SMU1 SMU2 SMU3 SMU4 USER F I1 I2 V1 V2 Rhos Sweep 0-10mA Com Mode I=0, Measure V1 Mode I=0, Measure V2 = = (V1-V2)/I1 / I Page 41

42 TEST SET UP FOR P+DS VAN DER PAUW Test Name: VDP-P+ SMU1 SMU2 SMU3 SMU Switch matrix R V1-V2 rhos SMU1 I1 Sweep 0-10mA I SMU2 SMU3 I2 V1 Com Mode I=0, Measure V1 Place Rochester a cursor Institute on of Technology the graph here to extract rhos value SMU4 USER F V2 Rc Mode I=0, Measure V2 = (V1-V2)/I1 Page 42

43 TEST SET UP FOR N+ CBKR Test Name: CBKR-N SMU1 SMU2 SMU3 SMU R Switch matrix V1-V2 Rc Place a cursor on the graph here to Rochester extract Institute Specific of Technology Contact Conductance value I SMU1 SMU2 SMU3 SMU4 USER F I1 I2 V1 V2 Rc Sweep 0-10mA Com Mode I=0, Measure V1 Mode I=0, Measure V2 = (V1-V2)/I1 Page 43

44 TEST SET UP FOR P+ CBKR Test Name: CBKR-P SMU1 SMU2 SMU3 SMU R Switch matrix V1-V2 Rc Place a cursor on the graph here to Rochester extract Institute Specific of Technology Contact Conductance value I SMU1 SMU2 SMU3 SMU4 USER F I1 I2 V1 V2 Rc Sweep 0-10mA Com Mode I=0, Measure V1 Mode I=0, Measure V2 = (V1-V2)/I1 Page 44

45 TEST SET UP FOR POLY CBKR Test Name: CBKRPOLY SMU1 SMU2 SMU3 SMU Switch matrix R V1-V2 Rc Place a cursor on the graph here to Rochester extract Institute Specific of Technology Contact Conductance value I SMU1 SMU2 SMU3 SMU4 USER F I1 I2 V1 V2 Rhos Sweep 0-10mA Com Mode I=0, Measure V1 Mode I=0, Measure V2 = (V1-V2)/I1 Page 45

46 TE02 TRANSISTORS Page 46

47 MOSFET IV CHARACTERISTICS Lot Number = F Wafer Number = D4 Date = Process = SMFL CMOS Product = DAC03 NMOS L/W = 2/16 NMOS Id-Vds Family of Curves NMOS Id-Vgs NMOS Subthreshold Characteristics NMOS Field VT NFAM NVT NSUB NFIELD PMOS L/W = 2/16 PMOS Id-Vds Family of Curves PMOS Id-Vgs PMOS Subthreshold Characteristics PMOS Field VT PFAM PVT PSUB PFIELD

48 MOSFET EXTRACTED PARAMETERS Lot Number = F Wafer Number = D4, Die Location R=, C= PMOS NMOS Units Mask Length / Width 2/16 2/16 µm VT V Lambda (for Vgs = Vdd) V -1 Max gm / mm of channel width S/mm Idrive µa/µm Vd = 0.1V 6 5 Decades Vd = 5V 7 6 Decades Vd = 0.1V 5.9e e-10 A/µm Vd = 5V 5.9e e-10 A/µm Sub-Vt Vd = 0.1V mv/dec Sub-Vt Vd = 5 V mv/dec DIBL@1nA/µm = V g / V d 0 0 mv/v Field VT V

49 TE02 TEST STRUCTURES Field FETs NMOS & PMOS test transistors Page 49

50 LARGE NMOS FAMILY OF CURVES SMU1 SMU2 SMU3 SMU4 Test Name: NFAM Switch matrix NMOS +Ids Saturation Region Vgs Vds Extract: Lambda L = 16 µm W = 8 µm SMU1 Vds Sweep 0-5 V, 101 steps SMU2 Vgs 11 Steps 0-5V SMU3 Com Vs = 0 SMU4 Page 50

51 LARGE NMOS ID-VGS Test Name: NVT SMU1 SMU2 SMU3 SMU Switch matrix Id gm Vto Vsub = volts +Vg Body Effect gm = did/dvg L = 16 µm W = 8 µm Extract: Max gm, Vto SMU1 SMU2 SMU3 SMU4 Vgs Com Sweep 0-5 V, 101 steps Vs = 0 Page 51

52 LARGE NMOS SUBTHRESHOLD Test Name: NSUB SMU1 SMU2 SMU3 SMU Switch matrix Id (Amps) Lights On Vt Sub Vt Slope (mv/dec) Vgs Extract: Imax, Imin, Sub Slope SMU1 SMU2 SMU3 SMU4 L = 16 µm W = 8 µm Vgs Com Sweep 0-5 V, 101 steps Vs = 0 Page 52

53 NMOS FIELD VT Test Name: NFIELD SMU1 SMU2 SMU3 SMU Switch matrix NMOS +Ids Saturation Region Vgs +Vds Extract: ~Vt SMU SMU1 SMU2 SMU3 Vds Vgs Com Sweep 0 to 20 V, 101 steps 11 Steps 0 to 20V Vs = 0 Page 53

54 LARGE PMOS FAMILY OF CURVES SMU1 SMU2 SMU3 SMU4 Test Name: PFAM Switch matrix NMOS +Ids Saturation Region Vgs Vds Extract: Lambda L = 16 µm W = 8 µm SMU1 Vds Sweep 0-5 V, 101 steps SMU2 Vgs 11 Steps 0-5V SMU3 Com Vs = 0 SMU4 Page 54

55 LARGE PMOS ID-VGS Test Name: PVT SMU1 SMU2 SMU3 SMU Switch matrix Id gm Vto Vsub = volts +Vg Body Effect gm = did/dvg L = 16 µm W = 8 µm Extract: Max gm, Vto SMU1 SMU2 SMU3 SMU4 Vgs Com Sweep 0-5 V, 101 steps Vs = 0 Page 55

56 LARGE PMOS SUBTHRESHOLD Test Name: PSUB SMU1 SMU2 SMU3 SMU Switch matrix Id (Amps) Lights On Vt Sub Vt Slope (mv/dec) Vgs Extract: Imax, Imin, Sub Slope SMU1 SMU2 SMU3 SMU4 L = 16 µm W = 8 µm Vgs Com Sweep 0-5 V, 101 steps Vs = 0 Page 56

57 PMOS FIELD VT Test Name: PFIELD SMU1 SMU2 SMU3 SMU4 NMOS Ids Switch matrix Saturation Region Vgs +Vds Extract: ~Vt SMU SMU1 SMU2 SMU3 Vds Vgs Com Sweep 0 to -20 V, 101 steps 11 Steps 0 to - 20V Vs = 0 Page 57

58 TE03 INTEGRATED CIRCUITS Page 58

59 TE03 TEST STRUCTURES Single Inverter Ring Oscillator Page 59

60 INVERTERS VOUT VIN +V Idd VOUT +V Voh Imax Slope = Gain VIN VO Idd VoL CMOS 0 0 D0 noise margin=vil-vol D1 noise margin=voh-vih ViL Vih Vinv +V VIN Page 60

61 INVERTER TEST SETUP SMU1 SMU2 SMU3 SMU4 Test Name: INV Switch matrix VOUT +V Voh VoL 0 0 Idd Imax VIN +V ViL Vih D0 noise margin=vil-vol D1 noise margin=voh-vih Extract: Rochester Voh, Institute Vol, of Technology Vih, Vil, Vinv, Imax, Gain SMU1 SMU2 SMU3 SMU Vdd Constant +5 V Vin Sweep 0 to +5V, 101 steps Vout I mode, measure Vout Com 0 Volts Page 61

62 TE03 RING OSCILLATOR Ring Oscillator Page 62

63 RING OSCILLATOR, td Seven stage ring oscillator with two output buffers td = T / 2 N td = gate delay N = number of stages T = period of oscillation Vout Vout T = period of oscillation Page 63

64 73 Stage Ring at 5V, td = 0.712ns 73 Stage Ring at 6V, td = 0.228ns

65 TE03 INSTRUCTIONS Move to manual probe station. Place wafer on stage and apply vacuum. Move stage such that Ring Oscillator is in the field of view. Move manual probes to make contact with the GND, OUT, and VDD probe pads. Use a DC power supply to supply 5 V to VDD, and 0 V to GND. Use the oscilloscope to view & measure the frequency. 17, 37 or 73 stages. Output: Open Folder name: Textronixoutput on desktop Open Program 7470 (DOS) Click Aquire; Request address number 7 Data will download to computer and plot will update Print plot or save as: filename.gif Page 65

66 OPERATIONAL AMPLIFIER +V M11 M10 M9 M8 L/W 40/10 40/10 40/10 10/20 5 Vin- M3 2 10/15 M1 M2 10/15 M5 M4 10/20 10/20 1 -V 10/20 4 Vin M6 M7 10/15 9 Vout 10/20 +V=+6 Vout +6 p-well CMOS dimensions L/W (µm/µm) Vin - + Vout Slope = Gain -V= mV Vos 0 Vin +20mV Set up the HP 4145 to sweep the Vin from -20 mv to +20 mv in 0.001V steps. Measure Gain and Input offset voltage. Page 66

67 AC TEST RESULTS ROCHESTER INSTITUTE OF TECHNOLOGY MICROELECTRONIC ENGINEERING LFF OPAMP.XLS FILE3B LOT F OPAMP TEST RESULTS Frequency Gain Vout Vin hz db V mv Gain db Op Amp Frequency Response Frequency Hz GBP = 500,000 Hz Page 67

68 TE04 Page 68

69 NMOS ID-VGS Test Name: NVT SMU1 SMU2 SMU3 SMU Switch matrix Id gm Vto Vsub = volts +Vg Body Effect gm = did/dvg L = 16 µm W = 8 µm Extract: Vto SMU1 SMU2 SMU3 SMU4 Vgs Com Sweep 0-5 V, 101 steps Vs = 0 Page 69

70 TE04 INSTRUCTIONS WAFER MAP Measure Vt for NFET on each die in a 15 x 15 array centered on the wafer. Record information in MESA and on an excel spreadsheet using the Binning described in below. Code 0 no die 1 value<(target-70%) 2 (Target-70%)<value<(Target-50%) 3 (Target-50%)<value<(Target-30%) 4 (Target-30%)<value<(Target-10%) 5 (Target-10%)<value<(Target+10%) 6 (Target+10%)<value<(Target+30%) 7 (Target+30%)<value<(Target+50%) 8 (Target+50%)<value<(Target+70%) 9 (Target+70%)<value Col 1 Row 1 Row 15 T T T T T T T T T T T T T T T T T T T T T T T T T T T T T T T T T T T T T T Col 15 Example Data nmos Vt target Page 70

71 Lot Number = F Wafer Number = D3 Family of curves for L=4µm MOSFETs 2µm/32µm L/W NMOS AND PMOS

72 SMFL CMOS DAC TEST STRUCTURES 8 7 S D Sub G /16 L/W NMOS FET Page 72

73 SMFL CMOS DAC TEST STRUCTURES 8 7 S D Sub G /16 L/W PMOS FET Page 73

74 SMFL CMOS DAC TEST STRUCTURES VAN DER PAUW AND CBKR Page 74

75 SMFL CMOS DAC TEST STRUCTURES 8 7 V+ Vo L = 2um INVERTERS Vin Gnd Page 75

76 SMFL CMOS DAC TEST STRUCTURES 37 STAGE 2um RING OSCILLATOR Page 76